The present invention relates generally to devices fabricated on thin silicon films, and more specifically the invention pertains to radiation-resistant silicon substrate and for high temperature operation of devices grown on insulating diamond films.
Recently, there has been increased interest in recrystallizing thin layers of semiconductor material, especially silicon, on a buried noncrystalline insulator layer as in, semiconductor-on-insulator technology. Typically, a layer of insulator material is formed on a semiconductor substrate and, patterned, a layer of semiconductor material, is deposited thereover, the semiconductor layer is melted in whole or in part, and one or more solidification fronts are caused to advance laterally across the semiconductor layer. See, for instance, U.S. Pat. No. 4,323,417, issued Apr. 6, 1982 to H. W. Lam, the disclosure of which is incorporated herein by reference. Electronic devices based on buried insulator structures offer promise of, increased dielectric isolation, useful in, high voltage-high power devices, reduced parasitic capacitance in integrated circuits, and of improved radiation hardness of devices. Common buried insulator is silicon dioxide. While these devices have proven excellent, the search continues for radiation resistant silicon substrate devices, which could operate at high temperatures.
A promising buried insulator candidate is diamond. Diamond films have a resistivity of 10.sup.16 ohm-cm, and are excellent electrical insulators. The task of producing a recrystallized silicon layer on diamond device is alleviated, to some extent, by the systems disclosed in the following U.S. Patents, the disclosures of which are incorporated herein by reference:
U.S. Pat. No. 4,444,620 issued to Kovacs et al;
U.S. Pat. No. 4,885,052 issued to Fan et al;
The use of silicon with diamond films is discussed in the article entitled "Silicon on Insulator using CVD Diamond Films" by K. V. Ravi and M. I. Landstrass. This paper was presented at the First International Symposium on Diamond and Diamond-Like Films by, in the Electrochemical Society Meeting, Los Angeles, Calif., May 1989, and is incorporated herein by reference.
Silicon-on-diamond is a form of silicon-on-insulator technology. Silicon-on-diamond with a very high electrical resistivity and thermal conductivity diamond film is suitable for developing high temperatures, high speed ultra large scale integrated (ULSI) circuits. This structure is suitable for radiation hardened applications. In silicon-on-diamond (SOD) technology, diamond replaces the silicon dioxide in the silicon-on-insulator structure. Diamond is a good thermal conductor, unlike silicon dioxide, and is a good electrical insulator, like silicon dioxide.